assume cs:code
code segment
    start:mov ax, 0
        ;读取CMOS RAM的2号单元内容
          mov al, 2
          out 70h, al
          in al, 71h
        
        ;向CMOS RAM的2号单元写入0
        mov al, 2
        out 70h, al
        mov al, 0
        out 71h, al

        mov ax, 4c00h
        int 21h
code ends
end start
